In U.S. Pat. No. 4,275,449 "Modelling Arrangements," Aish describes a set of building blocks as a computer input device for architectural applications. The blocks were geometric solids with connectors on some of the faces, and could be changeably interconnected to form different modeling arrangements whose geometric structure could be read by a computer. Each block had an identifier, which when used as an index into a file of information about the blocks, permitted 3-D renderings to be made of the physical model. Aish devised an approach to reading out the structure of a modeling arrangement that kept the circuitry in each block to a minimum. A host computer directed a search of the structure, selecting one block at a time. That block's identity was read, then neighbors detected and control passed from that block to a neighbor, and so on, until an exhaustive search of the structure had been completed.
Evans, in "Intelligent Building Blocks," Architect's Journal, Jan. 30, 1985, pp. 47-54, mentions that other information, such as material properties and costs, could also be associated with such blocks, permitting the computer to prepare various architectural analyses and reports about the modeled structures.
Frazer, in "An Evolutionary Architecture," Architectural Association, 1995, describes a more ambitious series of prototypes of machine-readable modeling tools. In general their approach to reading the modeling structure followed Aish's, although they tried several different kinds of building elements, and used them for a variety of applications. In one embodiment, each of Frazer's blocks had eight bits of state reflected in eight LEDs that could be controlled by a host computer. One of the blocks was equipped with six mercury tilt-switches to determine the orientation of the entire model. Another block had magnet-sensitive reed-switches embedded in external cladding panels. As the computer came to poll that block for its identify, the state of these switches could affect the result in a way that would in turn affect the virtual model's rendered appearance.
Frazer also developed a modeling kit whose elements corresponded to the components used in kits for building actual modular homes. The miniature modeling kit included a variety of elements such as wall panels, doors and windows. Software on the computer drew plans, gave feedback on planning errors, estimated costs and energy consumption, etc.
Dewey et al., in "Geometry-Defining Processors for Partial Differential Equations," B. J. Alder (ed.) "Special Purpose Computers," Academic Press, 1988, pp. 67-96, describe a set of 3-D blocks similar to some of those built by Frazer's group, but with a different application in mind. The motivation for their geometry-defining processors was to build a re-configurable parallel computer for finite-element simulations of systems studied in mechanical engineering. Thus, the connection geometry of the parallel processing elements could match the geometry of the underlying physical system being modeled, and thereby use the available communications bandwidth more efficiently. Because the principal goal was engineering computation, each building element contained a commercially available microprocessor.
Other related work is described by Gorbet et al. in "Triangles: A Physical-Digital Construction Kit," Proceedings of Designing Interactive Systems: Processes, Practices Methods and Techniques, August 1997, pp. 125-128, and in "Triangles: Tangible Interface for Manipulation and Exploration of Digital Information Topography," Proceedings of CHI 98, Apr. 1998, pp. 49-6. In the "Triangles" system, the basic building elements are triangles. Each triangle is a planar, plastic equilateral triangle with an embedded microprocessor. The triangles connect to each other physically and digitally with magnetic, electrically conducting connectors. When connected to each other, the triangles can be tiled on a flat surface, or folded over into more complex surface topologies. When the triangles are connected, information about their identities is exchanged, and messages can be relayed to a host computer. In this way, an application running on the host can determine relationships between the connected pieces, and specific connections can trigger specific digital events. Typical applications include visual programming, visual scripting, and pattern formation.
Key attributes desired of self-describing construction kits include: scalability--the ability to build large structures containing hundreds of building elements, configurability--the ability to connect building elements in rich and varied ways, interactivity--the ability to interact physically and electrically with a constructed artifact, and presentation--the ability to design customized and stylized visual and physical interpretations of constructed artifacts. Known prior art building block systems lack integrated solutions that address these key attributes.